U.S. patent application number 11/151514 was filed with the patent office on 2006-03-16 for vehicle-use automatic transmission device.
This patent application is currently assigned to HONDA MOTOR CO., LTD.. Invention is credited to Yoshiaki Hori.
Application Number | 20060053966 11/151514 |
Document ID | / |
Family ID | 35134405 |
Filed Date | 2006-03-16 |
United States Patent
Application |
20060053966 |
Kind Code |
A1 |
Hori; Yoshiaki |
March 16, 2006 |
Vehicle-use automatic transmission device
Abstract
A multi-stage automatic transmission is provided which includes
a small number of clutches in a vehicle-use automatic transmission
having a main shaft and a counter shaft.
Inventors: |
Hori; Yoshiaki; (Wako-shi,
JP) |
Correspondence
Address: |
HAMRE, SCHUMANN, MUELLER & LARSON, P.C.
P.O. BOX 2902-0902
MINNEAPOLIS
MN
55402
US
|
Assignee: |
HONDA MOTOR CO., LTD.
Minato-ku
JP
|
Family ID: |
35134405 |
Appl. No.: |
11/151514 |
Filed: |
June 13, 2005 |
Current U.S.
Class: |
74/640 |
Current CPC
Class: |
F16H 2200/0039 20130101;
Y10T 74/19 20150115; F16H 2200/0043 20130101; Y10T 74/19233
20150115; F16H 3/089 20130101; Y10T 74/19223 20150115; F16H 3/006
20130101 |
Class at
Publication: |
074/640 |
International
Class: |
F16H 35/00 20060101
F16H035/00 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 10, 2004 |
JP |
2004-232913 |
Claims
1. A vehicle-use automatic transmission device including a main
shaft and a counter shaft; the transmission device comprising: a
first group of driving gears which are fixed to an tubular
auxiliary main shaft which is concentrically and rotatably mounted
on the main shaft; a first group of follower gears which are
rotatably mounted on the counter shaft and are constantly meshed
with the first group of driving gears so as to be selectively
joined to the counter shaft; a first clutch which performs the
power engagement and power disengagement between the main shaft and
the tubular auxiliary main shaft; a second group of driving gears
which are rotatably mounted on the main shaft and are selectively
jointed to the main shaft; a second group of follower gears which
are fixed to an tubular auxiliary counter shaft which is
concentrically and rotatably mounted on the counter shaft and are
constantly meshed with the second group of driving gears; and a
second clutch which performs the power connection and disconnection
between the counter shaft and the tubular auxiliary counter
shaft.
2. A vehicle-use automatic transmission device according to claim
1, wherein either one of a first group of gears which are
constituted of the first group of driving gears and the first group
of follower gears and a second group of gears which are constituted
of the second group of driving gears and the second group of
follower gears is constituted of a group of odd-numbered-stage
gears and another group of gears is constituted of a group of
even-numbered-stage gears.
3. A vehicle-use automatic transmission device according to claim
1, wherein the transmission device further comprises a backward
driving gear which is fixed to the tubular auxiliary main shaft and
a backward follower gear which is rotatably mounted on the counter
shaft and is constantly meshed with the backward driving gear by
way of an intermediate gear so as to be selectively jointed to the
counter shaft.
4. A vehicle-use automatic transmission device according to claim
1, wherein the transmission device further comprises a backward
driving gear which is rotatably mounted on the main shaft and is
selectively joined to the main shaft and a backward follower gear
which is fixed to the tubular auxiliary counter shaft and is
constantly meshed with the backward driving gear by way of an
intermediate gear.
5. A vehicle-use automatic transmission device according to claim
1, wherein a means which selectively joins the gear to the shaft is
configured to include a shifter which is driven by an
electrically-operated motor and a means which is driven by the
shifter, is slidable in the axial direction and is engaged with or
is disengaged from the gear which is rotatable with respect to the
shaft.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to an automatic transmission
device of a vehicle-use power unit.
BACKGROUND OF THE INVENTION
[0002] FIG. 13 is a constitutional developed view of a conventional
power unit 01 which is mounted on a buggy car or the like including
respective rotary shafts thereof for example, see JP-A-2004-36835.
In the drawing, a left side (indicated by an arrow F) is a front
side of a vehicle. The power unit 01 is formed of an integral body
constituted of an internal combustion engine 02 and a transmission
03 and includes a crankshaft 04 which extends in the fore-and-aft
direction of a vehicle body, a main shaft 05 of the transmission, a
counter shaft 06 of the transmission 03, an output shaft 07 and a
backward driving changeover intermediate shaft 08. These rotary
shafts are arranged in parallel to each other and are rotatably
supported by front and rear crankcase members and a power is
transmitted to an output shaft 07 from the crankshaft 04 by way of
a transmission step. In this example, the internal combustion
engine 02 is a single-cylinder internal combustion engine, wherein
a piston 010 is connected to the crankshaft 04 by way of a
connecting rod 09 and the piston 010 performs the reciprocating
movement in a cylinder 011 to generate a power.
[0003] A torque converter 012 is mounted on a front end portion of
the crankshaft 04. The torque converter 012 is constituted of a
pump impeller 013 which is fixed to the crankshaft 04, a turbine
runner 014 which is freely rotatable while facing the pump impeller
013 in an opposed manner and a stator 015 which is held by a
crankcase member 017 by way of a one way clutch 016. To the turbine
runner 014 which is rotatable with respect to the crankshaft 04, a
primary driving gear 018 which is rotatable with respect to the
crankshaft 04 is integrally joined. A power generated by the
internal combustion engine 02 is transmitted to the pump impeller
013 from the crankshaft 04, is transmitted to the turbine runner
014 by way of a working oil and hence, the primary driving gear 018
is driven.
[0004] To a front end portion of the main shaft 05 of the
transmission, a primary follower gear 019 which is constantly
meshed with the primary driving gear 018 is fixed. The rotation of
the crankshaft 04 is transmitted to the main shaft 05 of the
transmission by way of a primary speed reduction which is
constituted of the primary driving gear 018 and the primary
follower gear 019. A first hydraulic multi-plate clutch 020 is
arranged close to the above-mentioned primary follower gear 019
fixed to the front end portion of the main shaft 05. A clutch outer
021 of the above-mentioned multi-plate clutch 020 is fixed to the
main shaft, while a clutch inner 022 is joined to a first-speed
driving gear M01 which is freely rotatable with respect to the main
shaft 05. To a rear portion of the main shaft 05 which extends
while penetrating the center of the first multi-plate clutch 020
and a center hole of the first-speed driving gear M01, a
second-speed driving gear M02 and a third-speed driving gear M03
are fixed.
[0005] To a front end portion of the counter shaft 06 which is
rotatably supported in parallel to the above-mentioned main shaft
05, a first-speed follower gear C01 which is constantly meshed with
the above-mentioned first-speed driving gear M01 is fixed. On a
center portion of the counter shaft 06, a second-speed hydraulic
multi-plate clutch 023 and a third-speed hydraulic multi-plate
clutch 026 are mounted. Both of clutch outers 024, 027 of the
above-mentioned clutches are fixed to the counter shaft 06. A
clutch inner 025 of the above-mentioned second-speed multi-plate
clutch 023 is joined to a second-speed follower gear C02 which is
freely rotatable with respect to the counter shaft 06, while a
clutch inner 028 of the above-mentioned third-speed multi-plate
clutch 026 is joined to a third-speed follower gear C03 which is
freely rotatable with respect to the counter shaft 06.
[0006] On a rear portion of the counter shaft 06, a forward output
gear 029 and a backward output gear 030 are mounted in a state that
these gears are rotatable with respect to the counter shaft 06.
Between both gears, a dog clutch 031 which is fitted on the counter
shaft 06 in spline fitting and is movable in the fore-and-aft
direction is provided. To a backward driving changeover
intermediate shaft 08 which is arranged close to and in parallel to
the counter shaft 06 and rotatably, a first intermediate gear 032
which is constantly meshed with the above-mentioned backward output
gear 030 and a second intermediate gear 033 which is constantly
meshed with an output follower gear 034 described later are fixed,
and both of these intermediate gears 032, 033 are interlocked with
each other by way of the backward driving changeover intermediate
shaft 08.
[0007] To the output shaft 07 which is arranged in parallel to the
above-mentioned counter shaft, an output shaft follower gear 034
which is constantly meshed with the above-mentioned forward output
gear 029 and the second intermediate gear 033 is fixed. An output
of the power unit 01 is transmitted to a front wheel from a front
end of the output shaft 07 and is transmitted to the rear wheel
from the rear end of the output shaft 07.
[0008] In the vicinity of the counter shaft 06, a forward and
backward changeover device 035 is provided. The forward and
backward changeover device 035 is constituted of a shift drum 036
which is rotatably supported in parallel to the counter shaft 06,
one shifter 037 which is driven in the fore-and-aft direction along
one cam groove which is formed in an outer periphery of the shift
drum 036, and a manual rotating device which serves to rotatably
drive the shift drum 036. The above-mentioned manual rotating
device is constituted of a shift spindle 038, a change lever 039
which is formed on an end portion of the shift spindle 038, a
sector gear 040 which is mounted on the shift spindle, and a gear
041 which is integrally formed on a shaft 036a of the shift drum
036 and is meshed with the above-mentioned sector gear 040. The
shifter 037 is engaged with the dog clutch 031 and moves the dog
clutch 031 in the fore-and-aft direction so as to perform the
changeover of the forward driving and the backward driving. Here,
an alternating current generator 042 which generates an electric
power by the rotation of the crankshaft 04 is mounted on the rear
end of the crankshaft 04.
[0009] In the above-mentioned transmission 03, the selection of the
forward driving and the backward driving is decided based on
whether, using the forward and backward changeover device 035, the
shifter 037 is moved to the forward output gear 029 side so as to
allow the dog clutch 031 to be engaged with the above-mentioned
gear 029 or the shifter 037 is moved to the backward output gear
030 side so as to allow the dog clutch 031 to be engaged with the
above-mentioned gear 030. The selection of the transmission ratio
in the forward driving state is determined based on which one of
three multi-plate clutches 020, 023, 026 is selectively connected
and which one of the gears M01, C02, C03 is selectively joined to
the shaft. Here, when the backward driving state is selected, the
first multi-plate clutch 020 is selectively connected so that the
first-speed driving gear M01 is selectively joined to the shaft.
The operation and the changeover of the hydraulic multi-plate
clutch are performed using a hydraulic device not shown in the
drawing. FIG. 14 is an automatic transmission manipulation table
which arranges the selective manipulations of the clutches and the
shifter in the above-mentioned conventional power unit.
[0010] However, since the conventional transmission adopts the
three-stage automatic transmission, there has been a demand for a
multi-stage automatic transmission having a larger number of
stages. Further, it has also been a task to reduce the number of
parts of a multi-plate clutch having a large weight.
[0011] Further, in the conventional transmission, to perform the
changeover of the forward driving and the backward driving, a
change lever is manually manipulated so as to change over gears,
the manipulation becomes cumbersome.
SUMMARY OF THE INVENTION
[0012] The present invention, which has overcome the
above-mentioned tasks, relates to a vehicle-use automatic
transmission device including a main shaft and a counter shaft,
wherein the transmission device comprises: a first group of driving
gears which are fixed to an tubular auxiliary main shaft which is
concentrically and rotatably mounted on the main shaft; a first
group of follower gears which are rotatably mounted on the counter
shaft and are constantly meshed with the first group of driving
gears so as to be selectively joined to the counter shaft; a first
clutch which performs the power connection and power disconnection
between the main shaft and the tubular auxiliary main shaft; a
second group of driving gears which are rotatably mounted on the
main shaft and are selectively jointed to the main shaft; a second
group of follower gears which are fixed to an tubular auxiliary
counter shaft which is concentrically and rotatably mounted on the
counter shaft and are constantly meshed with the second group of
driving gears; and a second clutch which performs the power
connection and disconnection between the counter shaft and the
tubular auxiliary counter shaft. The number of clutches having a
large weight is decreased to two and hence, it is possible to
provide a light-weighted multi-stage automatic transmission.
[0013] Further, the vehicle-use automatic transmission device may
comprise either one of a first group of gears which are constituted
of the first group of driving gears and the first group of follower
gears and a second group of gears which are constituted of the
second group of driving gears and the second group of follower
gears is constituted of a group of odd-numbered-stage gears and
another group of gears is constituted of a group of
even-numbered-stage gears. Since the odd-numbered stage gears and
the even-numbered stage gears are arranged in a state that these
gears are divided into the first group of gears and the second
group of gears, it is possible to avoid a situation that the
clutches and the gear selection and joining means are
simultaneously manipulated at the time of transmission whereby the
smooth transmission is ensured.
[0014] The vehicle-use automatic transmission device may further
comprise a backward driving gear which is fixed to the tubular
auxiliary main shaft and a backward follower gear which is
rotatably mounted on the counter shaft and is constantly meshed
with the backward driving gear by way of an intermediate gear so as
to be selectively jointed to the counter shaft. It is possible to
perform the light-weighted multi-stage automatic transmission
having the frontward and backward driving changeover function.
[0015] The vehicle-use automatic transmission device may further
comprise a backward driving gear which is rotatably mounted on the
main shaft and is selectively joined to the main shaft and a
backward follower gear which is fixed to the tubular auxiliary
counter shaft and is constantly meshed with the backward driving
gear by way of an intermediate gear. Accordingly, it is possible to
perform the light-weighted multi-stage automatic transmission in
another mode having the frontward and backward driving changeover
function.
[0016] The vehicle-use automatic transmission device may comprise a
means which selectively joins the gear to the shaft is configured
to include a shifter which is driven by an electrically-operated
motor and a means which is driven by the shifter, is slidable in
the axial direction and is engaged with or is disengaged from the
gear which is rotatable with respect to the shaft. Since the
selective fixing of the gear is performed using the
electrically-operated motor which is manipulated with a switch, the
transmission and the forward/backward changeover manipulation are
facilitated. Further, since the mechanical gear selection manual
lever is replaced with the switch which operates the
electrically-operated motor, a layout of a periphery of a handle
becomes concise.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 A constitutional developed view of power unit 1A
according to the first embodiment of the present invention.
[0018] FIG. 2 A view showing a first-speed starting
manipulation.
[0019] FIG. 3 A view showing a changeover manipulation from the
first speed to the second speed.
[0020] FIG. 4 A view showing a manipulation during the second-speed
cruising.
[0021] FIG. 5 A view showing a changeover manipulation from the
second speed to the third speed.
[0022] FIG. 6 A view showing a manipulation during the third-speed
cruising.
[0023] FIG. 7 A view showing a changeover manipulation from the
third speed to the fourth speed.
[0024] FIG. 8 A view showing a backward driving manipulation.
[0025] FIG. 9 An automatic transmission manipulation table in a
power unit of the present invention.
[0026] FIG. 10 An explanatory view of a power unit 1B according to
the second embodiment of the present invention.
[0027] FIG. 11 A constitutional developed view of a power unit 1C
according to the third embodiment of the present invention.
[0028] FIG. 12 A constitutional developed view of a power unit 1D
according to the fourth embodiment of the present invention.
[0029] FIG. 13 A constitutional developed view of a conventional
power unit.
[0030] FIG. 14 An automatic transmission manipulation table in the
conventional power unit.
DETAILED DESCRIPTION OF THE INVENTION
[0031] FIG. 1 is a constitutional developed view including
respective rotary shafts of a power unit 1A according to the first
embodiment of the present invention which is mounted on a buggy
vehicle or the like. In the drawing, a left side (indicated by an
arrow F) is a front side of a vehicle. The power unit 1A is formed
of an integral body. constituted of an internal combustion engine 2
and a transmission 3 and includes a crankshaft 4 which is arranged
to extend in the fore-and-aft direction of a vehicle body, a main
shaft 5 of the transmission, a counter shaft 6 of the transmission,
an output shaft 7 and a backward driving changeover intermediate
shaft 8. These rotary shafts are arranged in parallel to each other
and are rotatably supported by front and rear crankcase members and
a power is transmitted to an output shaft 7 from the crankshaft 4
by way of a transmission step. In this embodiment, the internal
combustion engine 2 is a two-cylinder internal combustion engine,
wherein pistons 10a, 10b are connected to the crankshaft 4 by way
of connecting rods 9a, 9b and the pistons 10a, 10b perform the
reciprocating movement in cylinders 11a, 11b respectively to
generate a power.
[0032] An AC power generator 38 which generates a power by the
rotation of the crankshaft 4 is mounted on a rear end of the
crankshaft 4, while a torque converter 12 is mounted on a front end
portion of the crankshaft 4. The torque converter 12 is constituted
of a pump impeller 13 which is fixed to the crankshaft 4, a turbine
runner 14 which is freely rotatable while facing the pump impeller
13 in an opposed manner and a stator 15 which is held by a
crankcase portion 17 by way of a one way clutch 16. To the turbine
runner 14 which is rotatable with respect to the crankshaft 4, a
primary driving gear 18 which is rotatable with respect to the
crankshaft 4 is connected. A power generated by the internal
combustion engine 2 is transmitted to the pump impeller 13 from the
crankshaft 4, is transmitted to the turbine runner 14 by way of a
working oil and hence, the primary driving gear 18 is driven.
[0033] To a front end portion of the main shaft 5 of the
transmission, a primary follower gear 19 which is constantly meshed
with the primary driving gear 18 is fixed. The rotation of the
crankshaft 4 is transmitted to the main shaft 5 of the transmission
3 by way of a primary reduction which is constituted of the primary
driving gear 18 and the primary follower gear 19.
[0034] A first hydraulic multi-plate clutch 20 is arranged close to
the above-mentioned primary follower gear 19 fixed to the front end
portion of the main shaft 5. A clutch outer 21 of the
above-mentioned multi-plate clutch 20 is fixed to the main shaft 5,
while to a clutch inner 22 of the above-mentioned multi-plate
clutch 20, a tubular auxiliary main shaft 23 which covers the
outside of a front half portion of the main shaft 5 and is
rotatable with respect to the main shaft 5 is joined and the
tubular auxiliary main shaft 23 is rotated together with the clutch
inner 22. To the tubular auxiliary main shaft 23, a first-speed
driving gear M1, a third-speed driving gear M3 and a backward
driving gear R1 are fixed in order from the front side.
[0035] On a rear portion of the main shaft 5 which extends in a
state that the main shaft 5 penetrates the center of the first
hydraulic multi-plate clutch 20 and the center hole of the tubular
auxiliary main shaft 23, a second-speed driving gear M2 and a
fourth-speed driving gear M4 are rotatably supported with respect
to the main shaft 5. Between these gears, a dog clutch Md which is
fitted on the main shaft 5 by spline fitting and is movable in the
fore-and-aft direction is provided.
[0036] On the backward driving changeover intermediate shaft 8
which is supported rotatably in parallel with the above-mentioned
main shaft 5, a backward first intermediate gear R2 which is
constantly meshed with the above-mentioned backward driving gear R1
and a backward second intermediate gear R3 which is interlocked
with the backward first intermediate gear R2 by way or the backward
changeover intermediate shaft 8 are mounted.
[0037] On a front half portion of the counter shaft 6 which is
rotatably supported in parallel to the above-mentioned main shaft
5, a first-speed follower gear C1 which is constantly meshed with
the above-mentioned first-speed driving gear M1 and a third-speed
follower gear C3 which is constantly meshed with the
above-mentioned third-speed driving gear M3 are rotatably
supported. Between these gears, a dog clutch Cd which is fitted on
the counter shaft 6 in spline fitting and is movable in the
fore-and-aft direction is provided. Close to and behind these
gears, a backward follower gear R4 which is constantly meshed with
the above-mentioned backward second intermediate gear R3 is
rotatably supported on the counter shaft 6. Behind the backward
follower gear R4, a dog clutch Rd which is fitted on the counter
shaft 6 in spline fitting and is movable in the fore-and-aft
direction is provided.
[0038] On a rear end portion of the counter shaft 6, a second
hydraulic multi-plate clutch 24 is mounted. A clutch outer 25 of
the above-mentioned multi-plate clutch 24 is fixed to the counter
shaft 6. To a clutch inner 26 of the above-mentioned multi-plate
clutch 24, a tubular auxiliary counter shaft 27 which covers the
outside of a rear half portion of the counter shaft 6 and is
rotatable with respect to the counter shaft 6 is joined. The
tubular auxiliary counter shaft 27 is rotated together with the
clutch inner 26. To the tubular auxiliary counter shaft 27, a
second-speed follower gear C2 which is constantly meshed with the
above-mentioned second-speed driving gear M2 and a fourth-speed
follower gear C4 which is constantly meshed with the
above-mentioned fourth-speed driving gear M4 are fixed in order
from the front side. A counter shaft output gear 28 is fixed to a
rearmost portion of the counter shaft 6.
[0039] To an output shaft 7 which is arranged in parallel with the
above-mentioned counter shaft 6, an output shaft follower gear 29
which is constantly meshed with the above-mentioned counter shaft
output gear 28 is fixed. An output of the power unit 1A is
transmitted to the front wheel from a front end of the output shaft
7 and is transmitted to the rear wheel from a rear end of the
output shaft 7.
[0040] A gear changeover device 30 is provided in the vicinity of
the main shaft 5 and the counter shaft 6. The gear changeover
device 30 is constituted of a shift drum 31 which is rotatably
supported in parallel to the main shaft 5 and the counter shaft 6,
three shifters consisting of a first shifter 32, a second shifter
33, a third shifter 34 which are driven in the fore-and-aft
direction along three cam grooves formed in an outer periphery of
the shift drum 31, and a drive device for rotatably driving the
shift drum 31 such as an electrically-operated motor 35. A gear 36
is mounted on a shaft 31a of the shift drum and is meshed with an
output pinion 35a of the above-mentioned electrically-operated
motor 35 by way of a group of speed reduction gears 37. Due to the
actuation of the above-mentioned electrically-operated motor 35,
the shift drum 31 is rotated to a suitable position and three
shifters 32, 33, 34 are selectively moved. The above-mentioned
first shifter 32 is meshed with the dog clutch Cd, the second
shifter 33 is meshed with the dog clutch Md and the third shifter
34 is meshed with the dog clutch Rd respectively so as to move
these dog clutches in the for-and-aft direction. The
electrically-operated motor 35 is manipulated by a switch mounted
on a handle.
[0041] In the above-mentioned transmission, the dog clutch Cd can
assume a first-speed-side position where the dog clutch Cd is
engaged with the first-speed follower gear C1, a third-speed-side
position where the dog clutch Cd is engaged with the third-speed
follower gear C3 and a neutral position in the midst of the
above-mentioned both positions. The dog clutch Md can assume a
second-speed-side position where the dog clutch Md is engaged with
the second-speed driver gear M2, a fourth-speed-side position where
the dog clutch Md is engaged with the fourth-speed driving gear M4
and a neutral position in the midst of the above-mentioned both
positions. The dog clutch Rd can assume a backward-side position
where the dog clutch Rd is engaged with the backward follower gear
R4 and a neutral position which is remote from the backward
follower gear R4.
[0042] The selective joining of the respective gears consisting of
the frontward first-speed to fourth-speed gears and the backward
gear with respect to the shaft is performed by moving the
above-mentioned dog clutches in the fore-and-aft direction by way
of three shifters thus allowing the dog clutches to be engaged with
the gears mounted rotatably with respect to the shaft thus
selectively joining the gears to the shaft. The positions of the
shifters are determined by cam grooves which are preliminarily
programmed and are formed in the shift drum. The rotation of the
shift drum is performed based on a control of the above-mentioned
electrically-operated motor 35. With respect to the position of the
first shifter 32, the front side is set as the first-speed-side
position, the rear side is set as the third-speed-side position and
the intermediate between both sides is set as the neutral position.
With respect to the position of the second shifter 33, the front
side is set as the second-speed-side position, the rear side is set
as the fourth-speed-side position and the intermediate between both
sides is set as the neutral position. With respect to the position
of the third shifter 34, the front side is set as the backward-side
position and the rear side is set as the neutral position.
[0043] FIG. 2 to FIG. 8 are explanatory views of the manipulation
of the above-mentioned transmission. The power generated by the
internal combustion engine 2 is transmitted to the primary driving
gear 18 by way of the crankshaft 4 and the torque converter 12. The
power transmission path up to this primary driving gear 18 is equal
irrelevant to the transmission mode. The above-mentioned
manipulation explanatory views indicate the power transmission
paths from the primary driving gear 18 to the output shaft follower
gear 29 corresponding to the transmission stages in a bold
line.
[0044] FIG. 2 is a view which shows the first-speed starting
operation. At this point of time, the first shifter 32 is shifted
to the first-speed side so as to allow the dog clutch Cd to be
meshed with the first-speed follower gear C1, the second shifter 33
is shifted to the second-speed side so as to allow the dog clutch
Md to be meshed with the second-speed driving gear M2, and the
third shifter 34 is held at the neutral position. Here, the third
shifter 34 is always held in the neutral position during the
forward driving. When the first multi-plate clutch 20 is connected
in the above-mentioned state, the vehicle travels with the
first-speed starting. The power from the primary driving gear 18 is
transmitted to the output shaft 7 by way of the primary follower
gear 19, the main shaft 5, the first multi-plate clutch 20, the
tubular auxiliary main shaft 23, the first-speed driving gear M1,
the first-speed follower gear C1, the counter shaft 6, the counter
shaft output gear 28 and the output shaft follower gear 29 and,
thereafter, the power is outputted to the wheel. Although the
second-speed driving gear M2 is fixed to the shaft by way of the
dog clutch Md, the second multi-plate clutch 24 is not connected
and hence, the power is not transmitted to the counter shaft 6.
[0045] FIG. 3 is a view which shows the changeover manipulation
from the first speed to the second speed. The positions of the
shifters are not moved and are held at positions taken in the first
speed shown in FIG. 2. By changing over the hydraulic pressure
supply destination from the first multi-plate clutch 20 to the
second multi-plate clutch 24 in such a state, the transmission to
the second speed is performed. The power from the primary driving
gear 18 is transmitted to the output shaft 7 by way of the primary
follower gear 19, the main shaft 5, the dog clutch Md, the
second-speed driving gear M2, the second follower gear C2, the
tubular auxiliary counter shaft 27, the second multi-plate clutch
24, the counter shaft 6, the counter shaft output gear 28, and the
output shaft follower gear 29.
[0046] FIG. 4 is a view showing the manipulation during the
second-speed cruising. The hydraulic pressure destination clutch is
held at the second multi-plate clutch 24 and is not changed. The
power transmission path is equal to the power transmission path of
the second speed shown in FIG. 3. As the preparation for changeover
to the third speed, the first shifter 32 is moved, the dog clutch
Cd which is disposed outside the second-speed power transmission
path is moved to the third-speed side from the first-speed side so
as to allow the dog clutch Cd to be meshed with the third-speed
follower gear C3.
[0047] FIG. 5 is a view showing the changeover manipulation to the
third speed from the second speed. The shifter positions are held
at the positions at the time of completion of the second-speed
cruising shown in FIG. 4 and are not moved. By changing over the
hydraulic pressure supply destination from the second multi-plate
clutch 24 to the first multi-plate clutch 20 in such a state, the
transmission to the third speed is performed. The power from the
primary driving gear 18 is transmitted to the output shaft 7 by way
of the primary follower gear 19, the main shaft 5, the first
multi-plate clutch 20, the tubular auxiliary main shaft 23, the
third-speed driving gear M3, the third-speed follower gear C3, the
dog clutch Cd, the counter shaft 6, the counter shaft output gear
28, and the output shaft follower gear 29.
[0048] FIG. 6 is a view showing the manipulation during the
third-speed cruising. The hydraulic pressure destination clutch is
held at the first multi-plate clutch 20 and is not changed. The
power transmission path is equal to the third-speed power
transmission path shown in FIG. 5. As the preparation for
changeover to the fourth speed, the second shifter 33 is moved, the
dog clutch Md which is disposed outside the third-speed power
transmission path is moved to the fourth-speed side from the
second-speed side so as to allow the dog clutch Md to be meshed
with the fourth-speed driving gear M4.
[0049] FIG. 7 is a view showing the changeover manipulation to the
fourth speed from the third speed. The shifter positions are held
at the positions at the time of completion of the third-speed
cruising as shown in FIG. 6 and are not moved. By changing over the
hydraulic pressure supply destination from the first multi-plate
clutch 20 to the second multi-plate clutch 24 in such a state, the
transmission to the fourth speed is performed. The power from the
primary driving gear 18 is transmitted to the output shaft 7 by way
of the primary follower gear 19, the main shaft 5, the dog clutch
Md, the fourth-speed driving gear M4, the fourth follower gear C4,
the second multi-plate clutch 24, the counter shaft 6, the counter
shaft output gear 28, and the output shaft follower gear 29.
[0050] FIG. 8 is a view showing the backward manipulation. The
first shifter 32 and the second shifter 33 are held at the neutral
positions, while the third shifter 34 is moved to the backward side
to allow the dog clutch Rd to be meshed with the backward follower
gear R4. When the first multi-plate clutch 20 is connected in such
a state, the vehicle moves backward. The power from the primary
driving gear 18 is transmitted to the output shaft 7 by way of the
primary follower gear 19, the main shaft 5, the first multi-plate
clutch 20, the tubular auxiliary main shaft 23, the backward
driving gear R1, the first intermediate gear R2, the second
intermediate gear R3, the backward follower gear R4, the dog clutch
Rd, the counter shaft 6, the counter shaft output gear 28 and the
output shaft follower gear 29. Since the first intermediate gear R2
and the second intermediate gear R3 are interposed, the counter
shaft 6, the output shaft 7 and the like are rotated in the reverse
direction so that the wheel is driven backwardly.
[0051] In the above-mentioned respective manipulation stages, the
manner of operation and the changeover of the hydraulic multi-plate
clutches are performed using a hydraulic device not shown in the
drawing.
[0052] In the constitution of the above-mentioned automatic
transmission, the groups of gears except for the backward driving
gears are given collective names. The group of gears which are
fixed to the tubular auxiliary main shaft which is subjected to the
power connection and disconnection with respect to the main shaft
by the first clutch is named as the first group of driving gears,
the group of gears which are mounted on the counter shaft, are
constantly meshed with the above-mentioned first group of driving
gears and are selectively joined to the counter shaft are named as
the first group of follower gears. Both of these groups of gears
are generally named as the first group of gears. Further, the group
of gears which are mounted on the main shaft and are selectively
joined to the main shaft are named as the second group of driving
gears, the group of gears which are fixed to the tubular auxiliary
counter shaft which is subjected to the connection and the
disconnection with respect to the counter shaft by the second
clutch and are constantly meshed with the above-mentioned second
group of driving gears are named as the second group of follower
gears and both of these groups of gears are generally named as the
second group of gears.
[0053] FIG. 9 is an automatic transmission manipulation table which
arranges the selective manipulations of the clutches and the
shifters in the power unit 1A of the above-mentioned first
embodiment. In the above-mentioned embodiment, the
odd-numbered-stage gears and the even-numbered-stage gears are
arranged in a divided manner as the first group of gears and the
second group of gears and hence, it is possible to prevent the
clutches and the selective joining means from being manipulated
simultaneously at the time of transmission whereby it is possible
to realize the smooth transmission.
[0054] FIG. 10 is an explanatory view of a power unit 1B according
to the second embodiment of the present invention wherein the
transmission of the power unit 1A of the first embodiment and the
transmission of the power unit 2B of the second embodiment are
depicted in parallel. In the drawing, the crankshaft, the torque
converter, the output shaft and the like are omitted. Although the
first group of gears are constituted of the odd-numbered stage
gears (first speed, third speed) and the second group of gears are
constituted of the even-numbered stage gears (second speed, fourth
speed) in the first embodiment, the second embodiment is configured
such that the position of odd-numbered stage gears and the position
of the even-numbered stage gears are exchanged thus constituting
the first group of gears using the even-numbered stage gears
(second speed, fourth speed) and the second group of gears using
the odd-numbered stage gears (first speed, third speed). That is,
to explain the second embodiment in more detail, the second-speed
driving gears and the fourth-speed driving gears constitute the
first group of driving gears, the second-speed follower gears and
the fourth-speed follower gears constitute the first group of
follower gears, the first-speed driving gear and the third-speed
driving gear constitute the second group of driving gears, and the
first-speed follower gear and the thirds-speed follower gear
constitute the second group of follower gears. Also in the power
unit 1B of the second embodiment, the even-numbered stage gears and
the odd-numbered stage gears are arranged in a divided manner into
the first group of gears and the second group of gears and hence,
it is possible to prevent the clutches and the selective joining
means from being manipulated simultaneously at the time of
transmission whereby it is possible to realize the smooth
transmission. Here, also in the second embodiment, the backward
gears are arranged substantially in accordance with the arrangement
of the backward gears in the first embodiment.
[0055] FIG. 11 is a constitutional developed view of a power unit
1C according to the third embodiment of the present invention. The
power unit 1C of this embodiment is, compared to the power unit 1A
of the first embodiment, characterized in that a fifth-speed
driving gear M5 is additionally fixed onto the tubular auxiliary
main shaft 23 close to the backward driving gear R1, a fifth-speed
follower gear is rotatably mounted on the counter shaft 6, and a
dog clutch Rx which is engaged with the backward follower gear and
the fifth-speed follower gear is provided in place of the backward
dedicated dog clutch Rd. In the drawing, members which do not
differ in functions from the corresponding members of the first
embodiment are given same symbols as the symbols used in the first
embodiment. According to this embodiment, it is possible to realize
the fifth-speed automatic transmission. Further, since the
odd-numbered gears and the even-numbered gears are collected and
are arranged in a divided manner into the first group of gears and
the second group of gears, in the same manner as the transmission
operation of the first embodiment, it is possible to perform the
smooth transmission. According to the present invention, the
present invention is not limited to the fifth-stage transmission of
this embodiment and the transmission in a multi-stage can be
realized in general.
[0056] FIG. 12 is a constitutional developed view of a power unit
1D according to the fourth embodiment of the present invention. The
power unit 1D of this embodiment is characterized in that the
positions of the group of backward gears shown in the first
embodiment are changed and gears S1 to S4 and a dog clutch Sd are
provided in place of the gears R1 to R4 and the dog clutch Rd.
Member which have identical functions as the member in the first
embodiment are given the same symbols used in the first embodiment.
In front of the second-speed driving gear M2 mounted on the main
shaft 5, a backward driving gear S1 which is rotatable with respect
to the main shaft 5 and a dog clutch Sd which is fitted on the main
shaft 5 in spline fitting and is movable in the fore-and-aft
direction are provided. On a backward changeover intermediate shaft
8 which is rotatably supported in parallel to the above-mentioned
main shaft 5, a backward first intermediate gear S2 which is
constantly meshed with the above-mentioned backward driving gear S1
and a backward second intermediate gear S3 which is interlocked
with the backward first intermediate gear S2 by way of the backward
changeover intermediate shaft 8 are provided. To a front side of
the tubular auxiliary counter shaft 27, a backward follower gear S4
which is constantly meshed with the above-mentioned backward second
intermediate gear S3 is fixed.
[0057] In performing the backward traveling, the first shifter 32
and the second shifter 33 are held at the neutral position, the
third shifter 34 is moved in the backward side so as to allow the
dog clutch Sd to be meshed with the backward driving gear S1. When
the second multi-plate clutch 24 is connected in this state, the
vehicle moves backwardly.
[0058] As has been explained heretofore, the embodiments can obtain
the following effects.
[0059] (1) The number of clutches having a large weight is
decreased to two and hence, it is possible to provide the
light-weighted multi-stage automatic transmission.
[0060] (2) Since the odd-numbered stage gears and the even-numbered
stage gears are arranged in a state that these gears are divided
into the first group of gears and the second group of gears, it is
possible to avoid the situation that the clutches and the gear
selection and joining means are simultaneously manipulated at the
time of transmission whereby the smooth transmission is
ensured.
[0061] (3) Since the selective fixing of the gears is performed
electrically-operated motor which is manipulated with a switch, it
is possible to easily perform the transmission and the frontward
and backward driving changeover manipulation.
[0062] (4) Since the mechanical gear selection manual lever is
replaced with the switch which operates the electrically-operated
motor, the layout of a periphery of a handle becomes concise.
[0063] Although embodiments of the present invention have been
described thus far, the present invention is not limited to the
examples in the drawings and the embodiments described above, and
various modification may be made without departing the scope of the
present invention, as a matter of course.
* * * * *